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Clinical Evaluation of Insect Repellent and Insecticide Treated Nets in Lao PDR

The recruitment status of this study is unknown. The completion date has passed and the status has not been verified in more than two years.
Verified July 2009 by London School of Hygiene and Tropical Medicine.
Recruitment status was:  Recruiting
Population Services International
Information provided by:
London School of Hygiene and Tropical Medicine Identifier:
First received: July 10, 2009
Last updated: July 13, 2009
Last verified: July 2009

Rural communities involved in agriculture are often at highest risk of insect-borne diseases in Southeast (SE) Asia.

Skin-applied insect repellents may prove a useful means of reducing mosquito-borne diseases for those people working outdoors in high risk areas.

This trial is evaluating the use of insect repellent (20% diethyltoluamide) to reduce incidence of malaria, Japanese Encephalitis and Dengue. The investigators will recruit up to 1000 households from 100 villages in rural Laos. In each house the investigators shall recruit up to 5 individuals. Half of households will be randomised to repellent, half to a placebo. All individuals will be provided with insecticide treated bed nets for use at night. All household occupants will be followed for 7 months to record malaria cases by Rapid Diagnostic Test every month. Blood spots will be collected at start and end of study to measure Japanese Encephalitis and Dengue. All positive cases will be promptly treated. Outcome will be reduction in number of malaria cases (primary outcome) and Dengue/Japanese Encephalitis (secondary outcomes).

Condition Intervention Phase
Malaria Dengue Japanese Encephalitis Drug: 20% deet insect repellent Drug: placebo control Phase 3

Study Type: Interventional
Study Design: Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Triple (Participant, Investigator, Outcomes Assessor)
Primary Purpose: Prevention
Official Title: Clinical Evaluation of Insect Repellent and Insecticide Treated Nets Against Malaria, JE & Dengue in Rural Communities in Lao PDR

Resource links provided by NLM:

Further study details as provided by London School of Hygiene and Tropical Medicine:

Primary Outcome Measures:
  • reduction in malaria incidence [ Time Frame: monthly over 7 months ]

Secondary Outcome Measures:
  • Reduction in Japanese Encephalitis and / or Dengue infections [ Time Frame: After 7 months intervention ]

Estimated Enrollment: 5000
Study Start Date: July 2009
Estimated Study Completion Date: June 2011
Estimated Primary Completion Date: December 2010 (Final data collection date for primary outcome measure)
Arms Assigned Interventions
Experimental: 20% deet insect repellent
experimental intervention
Drug: 20% deet insect repellent
skin-applied repellent lotion
Placebo Comparator: lotion without repellent active Drug: placebo control
Identical base formulation of lotion but without any deet active


Ages Eligible for Study:   5 Years to 70 Years   (Child, Adult, Senior)
Sexes Eligible for Study:   All
Accepts Healthy Volunteers:   Yes

Inclusion Criteria:

  • working in agriculture
  • available for monthly follow-up

Exclusion Criteria:

  • allergy to repellent
  • pregnant / breastfeeding
  Contacts and Locations
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Please refer to this study by its identifier: NCT00938379

Contact: Vanessa Chen-Hussey, MSc

Lao People's Democratic Republic
Rural villages in Attepu and Sekong Provinces, Laos PDR Recruiting
Pakse, Attepu, Lao People's Democratic Republic
Contact: Vanessa Chen-Hussey, MSc    856 (0)21 353 408 ext 116   
Principal Investigator: Vanessa Chen-Hussey, MSc         
Sponsors and Collaborators
London School of Hygiene and Tropical Medicine
Population Services International
Principal Investigator: Nigel Hill, PhD LSHTM
  More Information

Publications automatically indexed to this study by Identifier (NCT Number):
Responsible Party: Dr Nigel Hill, Head of Unit, Disease Control & Vector Biology Identifier: NCT00938379     History of Changes
Other Study ID Numbers: NHLAO1
Study First Received: July 10, 2009
Last Updated: July 13, 2009

Keywords provided by London School of Hygiene and Tropical Medicine:
vector control

Additional relevant MeSH terms:
Encephalitis, Japanese
Protozoan Infections
Parasitic Diseases
Arbovirus Infections
Virus Diseases
Flavivirus Infections
Flaviviridae Infections
RNA Virus Infections
Hemorrhagic Fevers, Viral
Brain Diseases
Central Nervous System Diseases
Nervous System Diseases
Encephalitis, Arbovirus
Encephalitis, Viral
Central Nervous System Viral Diseases
Infectious Encephalitis
Central Nervous System Infections
Insect Repellents
Protective Agents
Physiological Effects of Drugs processed this record on September 21, 2017